The European ITEA research project OSAmI (Open Source Ambient Intelligence) targets open source common foundations for a dynamic service-oriented platform which is able to personalize itself in large diversity of cooperating Software Intensive Systems (SIS). The initiative consists of a number of networked national sub-projects focussing on different areas as an approach for converging towards common technology foundations. Under the scope of OSAmI, NICS has designed and implemented an indoor localization system based on Wireless Sensor Networks as well as other embedded and wearable tecnologies [1]. The goal is to provide a lightweight system for secure and privacy-preserving proximity-based applications. The system is based on the removal of identifiable information from the packet headers, on the limitation of the transmission power of the devices and the use of symmetric key cryptography, in particular the AES standard, for the creation of dynamic application-layer pseudonyms. This scheme has been implemented over two different platforms, the Crossbow MICAz motes and the Texas Instruments eZ430-Chronos wrist-watch. The former is based on the TinyOS open-source operating system while the latter is based on the OpenChronos firmware. Additionally, the scheme was suscessfully integrated with a follow-me service provided by Telefonica I+D. Software deployment is a transversal are of interest in OSAmI. OSAmI services has to be distributed in a secure way to all participant nodes. For that purpose, NICS has implemented a mechanism for short-term certificates generation that allow developers to sign their software while uploading it to the OSAmI repository [2]. Our solution is based on OpenID for authentication and X.509 certificates for digital signatures.